Burning Odor From AC Vents

When I’m driving I sometimes smell something burning. This has only been happening for about a week, off and on. Usually it only happens when the AC is on and gets stronger when the AC is up high. I also hear a squealing noise when I first start the car. What’s wrong with my car?



Howdy there Sara

I would definitely get a mechanic to look into this ASAP. The noise you hear could be coming from the fan belt under the hood. The belt has a spring loaded tensioner that keeps constant tension on it so it will not make noise…..so something is not right if you can hear the belt squeal. Since you hear a belt noise and also have a smell coming from the air conditioner, I would be suspect of the air compressor under the hood.

There also could be a possibility that you have a leaking heater core. Feel the carpets under the dash on the passenger side. If they feel damp or oily you could be leaking antifreeze inside the vehicle. Check the antifreeze level inside the radiator to confirm you are in deed low on antifreeze.

The heater core is inside the dash so you can not see it but your mechanic can confirm it is the culprit with a “cooling system pressure test” that looks for antifreeze leaks. The noise could be coming from antifreeze leaking on the fan belt????


Austin Davis

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